Understanding HTTP server applications

The HTTPServer object is the foundation of all Node.js web applications. The object itself is very close to the HTTP protocol, and its use requires knowledge of this protocol. Fortunately, in most cases, you'll be able to use an application framework, such as Express, to hide the HTTP protocol details. As application developers, we want to focus on business logic.

We already saw a simple HTTP server application in Chapter 2, Setting Up Node.js. Because HTTPServer is an EventEmitter object, the example can be written in another way to make this fact explicit by separately adding the event listener:

import * as http from 'http';

const server = http.createServer();
server.on('request', (req, res) => {
  res.writeHead(200, {'Content-Type': 'text/plain'});
  res.end('Hello, World!\n');
});
server.listen(8124, '127.0.0.1');
console.log('Server running at http://127.0.0.1:8124');

Here...